Apparatus for coating discrete articles

ABSTRACT

Discrete articles are contained in a vessel. A container accommodates a body of liquid coating and communicates with the interior of the vessel. Applicator means is provided in the container and operative for transferring quantities of liquid coating into the vessel for coating the discrete articles therein whereby the surface area of each such article increases as a result of the application of the coating. Control means associated with the container and the applicator means serves for increasing the quantity of liquid coating transferred into the vessel in response to increases in the surface areas of the articles.

{United States Patent Niediek 1151/ 3,658,030 1 51 Apr. 25,1972

1541 APPARATUS FOR COATING DISCRETE ARTICLES 1 [72] Inventor: Giinter Niediek, Salzgittet-Ringelheim,

- Germany [73] Assignee: Schaper & Brummer K.G.,Salzgitter-Ringelheim, Germany [22] Filed: June 17, 1969 [21] Appl. No.: 833,999

[30] Foreign Application Priority Data June 25, 1968 Germany., ..P 17 57 847.1

521 u.s. c1 1. ..11s/7,11s/19,11s/24, 118/303,]18/DIG. 16 51 1111.0. ..B05c 5/00, B05c 11/10 [58] FieldofSearch ..118/7,l9,303,323,300$, '118/32324, DIG. 16

[56] References Cited UNITED STATES PATENTS 2,261,988 ll/l94l Gaebel ..118/7 X 2,289,686 7/1942 Sooy ..1 18/7 X 2,293,201 8/1942 Gaebel 18/7 X 2,736,288 2/1956 Clay et a1 ..1 18/19 2,865,325 12/1958 Leston et all ..l18/300 S 3,141,792 7/1964 Lachman et a1. ..1 18/303 X 3,381,659 5/1968 Rieltmann et a1 ..1 18/19 Claus .l18/323 X Primary Examiner JOhn P. McIntosh Attorney-Michael S. Striker "[57] p 1 ABSTRACT Discrete articles are contained in a vessel. A container accommodates a body of liquid coating and communicates with the interior of the vessel. Applicator means is provided in the container and operative for transferring: quantities of liquid coating into the vessel for coating the discrete articles therein whereby the surface area of each such article increases as a result of the application of the coating. Control means associated with the container and the applicator means serves for increasing the quantity of liquid] coating transferred into the vessel in response to increases in the surface areas of the articles.

4 Claims, 4 Drawing Figures 1 APPARATUS FOR COATING DISCRETE ARTICLES BACKGROUND OF THE INVENTION The present invention relates generally to an apparatus for coating discrete articles and more particularly to an apparatus for coating such discrete articles as candies, pills, lozenges, dragees, and the like.

The coating of discrete articles, such as candies, pills for medicinal and other purposes, and the like, is still to a quite significant extent depending on manual operations which is of course time consuming and expensive. Such coating is for the purpose of increasing the aesthetic appearance of the articles and/or for taste reasons, such as sugar coating, chocolate coating, or the like. Other reasons for applying coatings are of course also well known.

There is available a variety of apparatuses provided with program control means intended to eliminate manual coating procedures. However, all of such apparatuses are complicated and expensive, and therefore subject to frequent maintenance problems and breakdowns. Alternately, they can be used only for special applications and/or with special coating substances.

It has been ascertained, however--and the present invention is based on this realization-that as the application of coating to discrete particles proceeds, the surface area of these particles increases so that during the coating process an increase should take place in the quantity of coating material being applied to the discrete articles from the beginning to the end of the coating process.

SUMMARY OF THE INVENTION It is, accordingly, an object of the present invention to provide an apparatus capableof effecting such an increase.

More particularly it is an object of the present invention to provide a simple, reliable and therefore inexpensive apparatus for this purpose.

An additional object of the invention is to provide such an apparatus which can accomplish its intended function automatically.

In pursuance of the above objects, and others which will become apparent hereafter, one feature of my invention resides in the provision of an apparatus for coating discrete articles which comprises, briefly stated, a nessel adapted to contain a plurality of discrete articles, a container having an interior communicating with the interior of the vessel and arranged to contain a body of liquid coating, and applicator means in the container operative for transferring quantities of liquid coating into the vessel for coating the discrete articles contained therein, whereby the surface area of each such article increases as a result of the application of such coating. Finally I provide control means associated with the container and the applicator means and operative for increasing the quantity of liquid coating which is transferred into the vessel per unit of time and concomitantly with increases in the surface areas of the articles.

The operation of my novel apparatus is in contrast with the apparatuses which exist and are known to me from the prior art. Heretofore there are either no increases in the quantity of coating which is admitted into the vessel, or the increase is manually adjusted. In the first case a median value is selected so that at the beginning of the coating process too much coating substance is applied whereas towards the end too little coating substance is applied. This quite frequently can lead to an unacceptable surface condition of the coated articles. In the other case manual adjustments are made on the apparatus for the purpose of increasing the quantity of coating substance which is admitted into the vessel containing the discrete articles during the coating process. This need take place only approximately at intervals of 4 hours and therefore does not usually present a problem during the daytime. However, particularly at night or if only a skeleton staff is available, this is quite disadvantageous because the attention of an operator is required even ifonly at these intervals.

It is emphasized that in the coating of discrete articles there are four basic coating steps involved, namely first the application of the layer which coats the core, that is the actual discrete article, thereupon the so-called smoothing layer, thereupon the color layer and finally the polish layer.

Of course, if the coating process is automatically operated, then it is advantageous and indeed necessary for economic reasons to combine as many of these individual steps as possible. It is therefore customary to use a solution wherein the substances for the first or adhering layer as well as the smoothing layer and the color layer are contained. Thus, a single coating step suffices to coat the discrete article completely, except for the final polishing layer. In accordance with the invention it is a further purpose to assure that the quantity of coating liquid which is to be applied can be automatically varied.

In accordance with the solution proposed under the invention there is an automatic regulation provided for continuous or intermittent regulation of the period during which the coating liquid is applied, or for varying the quantity of coating liquid in the container thereof to conform it to the increasing surface areas of the articles and to thereby obtain a change in the quantity of coating liquid applied, as still to be discussed.

The apparatus according to the present invention is rather simple in its construction, requires no special substances for use, does not require a special composition 'of the coating suspension or solution, and is largely free from maintenance problems. Furthermore, it can be readily used with existing equipment whose capacity is increased without the need for additional personnel. In fact, with the apparatus according to the present invention coating processes may be carried out without the need for human supervision, for instance at night, on holidays and the like. Thus articles may be coated automatically during a weekend pe 0d and at the first of the week they are available for undergoiilga polish coating process and are then ready.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING DESCRIPTION OF THE PREFERRED EMBODIMENTS Discussing now firstly FIG. 1 it will be seen that it illustrates an apparatus for coating discrete articles, such as candies, medical or other pills, and the like. It uses a conventional coating vessel 1 into which there extends a distributor container 2 which accommodates a body of the coating liquid. This body is identified with reference numeral 4 and it will be seen that mounted for rotation in the container 2 is a roller 3 provided with bristles which dip into the body 4 as the roller 3 rotates. An abutment 5 which is height-adjustable is provided adjacent the outlet of the container 2 which communicates with the, interior of the vessel 1 and is located in the path of the bristles of the roller 3 so that the same contact the abutment and are flexed thereby.

It is conventional to provide a conduit 6 which communicates with the interior of the container 2 and through which the latter is supplied with the coating liquid 4. This is shown in broken lines in F IG. 1 and it is emphasized that this possibility exists in the apparatus according to the present invention.

However, it is preferred that the coating liquid 4 be supplied from a supply container 7 via a conduit 11 in which a solenoid valve is interposed. A stirring device 9 driven by a motor 8 is provided in the container 7.

A float 12 is arranged in the container 2 and is operatively associated with the solenoid valve 10 in such a manner-not illustrated but known to those skilled in the artthat the liquid level in the container 2 will always be identical so thatgiven identical rotation of the roller 3 during an identical period of time-an identical quantity of coating liquid will be transferred by the bristles onto the discrete articles contained in the vessel 1. It will be appreciated that the abutment 5 is provided so that the bristles contact the same and are thereby flexed during continued rotation of the roller 3, with the result that when they finally move beyond the abutment 5, they fling the coating liquid adhering to them into the vessel 1 and into contact with the discrete articles therein.

Reference numeral 13 diagrammatically indicates a program control device which can control the operation of all operating steps of the apparatus, and such devices are well known to those skilled in the art, and are not believed to require detailed discussion.

It will be appreciated that with the embodiment of FIG. 11 an identical quantity of coating liquid 4 is always available in the container 2, independent of the progressive coating of the articles in vessel 1. The roller 3 can of course be driven in suitable manner, for instance by a motor which is not illustrated. The stirring device 9 in the supply vessel 7 prevents a settling of the suspension so that it can be used with many different suspensions. Such stirring device 9 may be used continuously or intermittently, and in the latter case it may be controlled by a timer or the like.

The device illustrated in FIGS. 2 and 3 serves to conform the quantity of coating liquid to be transferred into the vessel 1 per time unit, to the surface of the discrete articles in the vessel 1 which surface area increases as the coating process progresses. Reference numeral 14 is a gear arrangement which is associated with a small electromotor 5. A toothed belt 16 or analogous member is trained about an adjusting knob 17 for the setting of a timer 18 which effects setting of the time period for which coating liquid is applied. In dependence upon operation of the electromotor 15, the toothed belt 16 advances and turns the knob 17 to thereby effect continuous or intermittent changes in the setting of the knob 17, and whereby changes in the period of time during which coating liquid is applied and concomitantly of course changes in the quantity of applied coating liquid. The initial setting may of course be made manually.

FIG. 4, finally, shows an arrangement wherein the quantity of coating liquid .to be supplied is controlled not by the time period during which it is applied, but by a contact member 19 which regulates the level or quantity of coating 4 in the container 2. The contact member 19 comprises a metallic plate 20 and an insulating body 21 secured thereto. A feeler member 22 is mounted in the insulating body 21 and has its upper end constructed as a nut 23 with a hand wheel 24. Grooves are provided in the nut into which a snap-action ball 27 is pressed under the force of a spring 26.

An electromotor 28 is provided with a gear 29 and turns a spindle 30 which may consist of polyamide or the like, and which is threaded into the nut 23. A conductor 31 is secured to the spring 26 and another conductor is secured to the metallic plate 20, both of them being operatively associated with a magnet valve, for instance the solenoid valve 10 interposed in the conduit 11.

The contact member 19 replaces the float 12 shown in FIG. 1 and it will be appreciated that, when the solenoid valve 10 is opened and permits coating liquid to flow through the conduit 11 into the container 2, the level of liquid 4 in the container 2 rises. As soon as the level of liquid has risen so that it contacts the member 22, the solenoid valve 10 is closed. A timer or analogous instrumentality serves at predetermined time intervals to actuate the electromotor 18 which then rotates the spindle in a sense lifting the member 22 higher, thereby causing the solenoid valve 10 to be opened and additional'coating liquid to be admitted into the container 2. Alternatively the motor 15 may be operated continuously and the gearing 14 be provided with a step-down arrangement so that the member 22 is continuously and evenly lifted. This, of course, causes the level of coating liquid 4 in the container 2 to rise continuously, whereby a continuous increase is provided in the quantity of coating liquid which is transferred per time unit from the bristles of the roller 3 into the interior of the vessel 1. Again, the starting setting of the member 19 can be carried out manually.

The versatility of my novel apparatus is great and it may be used for a wide range of purposes, not only for coating medicinal articles such as pills or the like, but also for coating candies, nuts with chocolate, or the like. As pointed out earlier, once set for the initial starting point it can operate fully automatically and requires no supervision. It can therefore be used at night, on holidays, weekends and the like and will produce semi-finished coated articles which, on the next working day, need only be subjected to the final polish coating.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of applications differing from the types described above.

While the invention has been illustrated and described as embodied in an apparatus for coating discrete articles, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Iclaim:

1. An apparatus for coating discrete articles, comprising a vessel adapted to contain a plurality of discrete articles; a container having an interior communicatingwith the interior of said vessel, and arranged to contain abody of liquid coating material; applicator means in said container and operative for transferring quantities of said liquid coating material into said vessel for coating the discrete articles contained therein, whereby the surface area of each such article increases as a result of the application of such coating; and control means associated with said container and applicator means for effecting a rise in the level of liquid coating material in said container with concomitant increase in the quantity of coating material being transferred into said vessel, said control means including an electrically conductive member having a leading end and being located in said container proximal to and above said body of liquid coating material, motor means associated with said conductive member for moving said leading end thereof relative to the level of said body of liquid coating material, admitting means for admitting additional coating material into said container, and an electrical connection associated with said member, motor means and admitting means for actuating the latter in a sense resulting in admission of additional liquid coating material into said container in response to movement of said leading end out of said body and upwardly above said level.

2. An apparatus as defined in claim 1, said applicator means comprising a rotary element mounted in said container and provided with bristles positioned so as to dip into said body of liquid coating material during rotation of said rotary element.

3. An apparatus as defined in claim 2, said container having an opening proximal to said rotary element and communicating with said vessel; and further comprising abutment means arranged at said opening and positioned for engaging the bristles of said rotary element during rotation of the latter, so as to flex said bristles and thereby facilitate flinging of liquid coating material adhering to said bristles through said opening into said vessel.

4. An apparatus as defined in claim 3, wherein said abutment means is adjustable.

- Patent-No, 13.5%

and t (SEAL) Attest:

It; is certified that error appears in the above- 7 hat 'saidL'etters Patent are hereby correctedas 1 On-the coversh' ee t [30]" "June 2 5;

EDWARD M.FLETCHER",JR; j a. A t n 'Q i r;

UNITED STATES PATENT OFFICE CERTIFICATE O CORRECTION Dated K131611125; 19:72

id'nti fie d atent 7 shown below:

: lassfshoul i aa 11 Signed ahd sea ledj this 26th jay of f De ember -;912;; 1

HROBERT GOTTSCI iALK Commissioner jbfg Pat ents o Po-mso (10-69) uscoMM-oc wan-P69 US. GOVERNMENT PRIN'IilNG OFFICE "ID 0-355-33l, 

1. An apparatus for coating discrete articles, comprising a vessel adapted to contain a plurality of discrete articles; a container having an interior communicating with the interior of said vessel, and arranged to contain a body of liquid coating material; applicator means in said container and operative for transferring quantities of said liquid coating material into said vessel fOr coating the discrete articles contained therein, whereby the surface area of each such article increases as a result of the application of such coating; and control means associated with said container and applicator means for effecting a rise in the level of liquid coating material in said container with concomitant increase in the quantity of coating material being transferred into said vessel, said control means including an electrically conductive member having a leading end and being located in said container proximal to and above said body of liquid coating material, motor means associated with said conductive member for moving said leading end thereof relative to the level of said body of liquid coating material, admitting means for admitting additional coating material into said container, and an electrical connection associated with said member, motor means and admitting means for actuating the latter in a sense resulting in admission of additional liquid coating material into said container in response to movement of said leading end out of said body and upwardly above said level.
 2. An apparatus as defined in claim 1, said applicator means comprising a rotary element mounted in said container and provided with bristles positioned so as to dip into said body of liquid coating material during rotation of said rotary element.
 3. An apparatus as defined in claim 2, said container having an opening proximal to said rotary element and communicating with said vessel; and further comprising abutment means arranged at said opening and positioned for engaging the bristles of said rotary element during rotation of the latter, so as to flex said bristles and thereby facilitate flinging of liquid coating material adhering to said bristles through said opening into said vessel.
 4. An apparatus as defined in claim 3, wherein said abutment means is adjustable. 